Tarallo L, et al. - A total of 131 consecutive patients who underwent open reduction and internal fixation of isolated closed Mason type II radial head fracture (RHF) were retrospectively cataloged to ascertain the lateral ulnar collateral ligament (LUCL) injury correlated with isolated RHF and the association of the ligament injury with the displacement of the fragment—loss of contact—in unstable displaced partial articular RHF in individuals without any history of ulnohumeral dislocation. Preoperative radiographs of the 131 patients presented 101 nonseparated fractures and 30 unstable fractures. In 18 elbows, anterior displacement of the fragment was discovered and posterior displacement in 12. In 18 of 30 unstable RHFs and in 1 of 60 stable RHFs, LUCL avulsion was obtained. Therefore, RHF is a complex fracture frequently correlated with soft tissue lesions. It is necessary to discover which structures require to be improved to circumvent complications that could result in elbow instability. The RHF pattern and classification as stable or unstable could assist the surgeon in the recognition and treatment of LUCL lesions.